Star slugger Bryce Harper slipped while trying to beat out an infield hit in the first inning Saturday night, and he immediately collapsed in pain holding his lower left leg.

Nationals manager Dusty Baker did not have much additional information following the game, but general manager Mike Rizzo announced on Sunday that Harper suffered has “significant bone bruise” but avoided ligament damage. The team is hopefully that he will be able to return this season but he’s headed to the 10-day disabled list.

The Nationals and the Giants were rained out Friday night, and more inclement weather delayed the start of Saturday’s game by about three hours. Rain continued to come down in the nation’s capital, but MLB decided to go ahead with the game. Harper skidded across the bag and landed awkwardly on his left foot. When his right foot landed, Harper flipped up into the air, landing with a thud.

Harper stayed down for several minutes, writhing in pain as the training staff and coaches attended to their superstar player. Eventually he was propped up and carried off on the shoulders of two assistants. He did not put any weight on the leg.

Harper is hitting .327 with 29 home runs and 87 runs batted in this year and was a strong candidate for his second NL MVP award.

It’s been a trying year for the team on the injury front. Earlier in the year, starting centerfielder Adam Eaton tore his ACL on a very similar play to Harper’s. Currently, starting left fielder Jayson Werth, starting shortstop Trea Turner and star pitcher Stephen Strasburg are all on the DL as well. Another starter, Joe Ross, is out for the year after recently undergoing Tommy John surgery.